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<table width="100%" summary="page for arthritis"><tr><td>arthritis</td><td style="text-align: right;">R Documentation</td></tr></table>

<h2>Rheumatoid Arthritis Clinical Trial</h2>

<h3>Description</h3>

<p>Rheumatoid self-assessment scores for 302 patients, measured on a five-level
ordinal response scale at three follow-up times.
</p>


<h3>Usage</h3>

<pre>
arthritis
</pre>


<h3>Format</h3>

<p>A data frame with 906 observations on the following 7 variables:
</p>
 <dl>
<dt>id</dt><dd><p>Patient identifier variable.</p>
</dd>
<dt>y</dt><dd><p>Self-assessment score of rheumatoid arthritis measured on a
five-level ordinal response scale.</p>
</dd> <dt>sex</dt><dd><p>Coded as (1) for
female and (2) for male.</p>
</dd> <dt>age</dt><dd><p>Recorded at the baseline.</p>
</dd>
<dt>trt</dt><dd><p>Treatment group variable, coded as (1) for the placebo
group and (2) for the drug group.</p>
</dd> <dt>baseline</dt><dd><p>Self-assessment
score of rheumatoid arthritis at the baseline.</p>
</dd>
<dt>time</dt><dd><p>Follow-up time recorded in months.</p>
</dd> </dl>



<h3>Source</h3>

<p>Lipsitz, S.R. and Kim, K. and Zhao, L. (1994) Analysis of repeated
categorical data using generalized estimating equations. <em>Statistics in
Medicine</em>, <b>13</b>, 1149&ndash;1163.
</p>


<h3>Examples</h3>

<pre>
data(arthritis)
str(arthritis)
</pre>


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